Paul Reimer showed these two slides at the

Paul Reimer showed these two slides at the Jlab User’s Group meeting: I have shamelessy copied them…. . NNPSS 2009 E. Beise, U Maryland 1

NNPSS 2009 E. Beise, U Maryland 2

Hadron Physics Topics I will attempt to cover: Lecture #1: The quark model, QCD, and hadron spectroscopy Lecture #2: Internal structure of hadrons: momentum and spin Lecture #3: Internal structure of hadrons: charge, magnetism, polarizability Lecture #4: Hadrons as laboratories (and other miscellaneous topics) NNPSS 2009 E. Beise, U Maryland 3

caveats I am an experimentalist! I will focus on what we know and how we measure it I will not give a rigorous presentation of theory by any stretch. I am not an expert on most of these topics: I will borrow heavily from the work of others. In particular presentations from recent conferences and past summer schools. Recent Conferences are: Workshop of the APS Topical Group on Hadronic Physics (GHP): Denver, 2009 http: //www. fz-juelich. de/ikp/ghp 2009/Program. shtml Conference on the Intersections between Nuclear and Particle Physics (CIPANP), San Diego 2009 http: //groups. physics. umn. edu/cipanp 2009/program. html Jefferson Lab Users Annual Meeting, June 2009 http: //conferences. jlab. org/ugm/program. html NNPSS 2009 E. Beise, U Maryland 4

some references Halzen & Martin: Quarks and Leptons F. E. Close: An Introduction to Quarks and Partons Perkins: Introduction to High Energy Physics Cahn and Goldhaber: The Experimental Foundations of Particle Physics Xiangdong Ji: Graduate nuclear physics lecture notes http: //www. physics. umd. edu/courses/Phys 741/xji/lecture_notes. htm Lectures from the Hampton University Graduate School (HUGS): http: //www. jlab. org/hugs/archive/ Lectures from past Nuclear Physics Summer Schools (most are available online) and I have shamelessly borrowed material from wherever I could find it. Special thanks to (for nice review slides) Zein-Eddine Meziani, Temple University (spin, DIS) Naomi Makins, University of Illinoisn (spin, transversity) Volker Burkert, Jefferson Lab (N* physics) Volker Crede, Florida State University (glueballs) NNPSS 2009 E. Beise, U Maryland 5

The big picture What are the questions? What are the connections between this topic and other areas of nuclear physics? NNPSS 2009 E. Beise, U Maryland 6

The Questions of the 2007 Long Range Plan • Quantum Chromo. Dynamics – What are the phases of strongly interacting matter? – What is the internal landscape of nucleons? – What governs the transition of quarks and gluons into nucleons and pions? • Nuclei and Nuclear Astrophysics – What is the nature of the nuclear force? – What is the origin of simple patterns in complex nuclei? – What is the origin of the elements in the cosmos? • Symmetries and Neutrinos http: //www. sc. doe. gov/np/nsac. html NNPSS 2009 – What is the nature of neutrinos? – Why is there now more visible matter than antimatter? – … and of course more…. E. Beise, U Maryland 7

Landscape of Nuclear Physics relativistic heavy ions electron scattering stable and radioactive beams few body heavy nuclei quarks gluons vacuum From W. Nazarewicz, ORNL

Jefferson Laboratory (Newport News, VA) present 12 Ge. V Upgrade E ~ 6 Ge. V Continuous Polarized Electron Beam > 100 m. A up to 85% polarization concurrent to 3 Halls Feb 2008 Elizabeth Beise, U Md 9

Hadron Physics Lecture #1: The quark model, QCD, and hadron spectroscopy Lecture #2: Internal structure of hadrons: momentum and spin Lecture #3: Internal structure of hadrons: charge, magnetism, polarizability Lecture #4: Hadrons as laboratories (and other miscellaneous topics) NNPSS 2009 E. Beise, U Maryland 10

The atom (slide from R. De. Vita, AAAS meeting, Feb 2008) Our present knowledge on the atomic structure of matter was obtained through a series of experimental observations and theoretical advances • In 1803 J. Dalton postulated the existence of chemical elements introduced to explain the variety of known compounds • Discovery of the electron by J. J. Thomson in 1867 and its studies on isotopes destroy the concept of the atom as indivisible particle • The “gold foil” experiment by E. Rutherford and the development of Quantum Mechanics led to the modern models of atomic structure proton neutron NNPSS 2009 E. Beise, U Maryland 11

http: //www. cpepweb. org E. Beise, U Maryland 12

observation of hadron states + Chicago Cyclotron: beams of + and - from 50 -180 Me. V ratio of production cross sections (9: 2: 1) consistent with all three processes going through a single common resonance with Isospin 3/2. The authors suggest looking at the angular distribution in order to determine the state’s total angular momentum…. NNPSS 2009 E. Beise, U Maryland 13

angular distributions From “phase shift analysis”, assuming only S and P waves, found that resonance was associated with I=3/2, J=3/2 (early example of electronics diagram in a paper!) NNPSS 2009 E. Beise, U Maryland 14

(slide from R. De. Vita, AAAS meeting, Feb 2008) strangeness: The V particle EVIDENCE FOR THE EXISTENC OF NEW UNSTABLE ELEMENTARY PARTICLES G. D. Rochester and C. C. Butler, Nature 160 (1947) 855. Tracks observed in a cloud chamber photographs, exposed to cosmic rays 2 photographs out of 5000 showed forked tracks Surprisingly long life time (10 -10 s) compared w/ typical production reactions: → weak decay K 0 p+ masses of outgoing tracks could only be estimated, but < proton mass. New property called strangeness was introduced: conserved in strong interactions but violated in weak interactions. NNPSS 2009 E. Beise, U Maryland p 15

Experiments Experimental requirements for hadron spectroscopy: energy (accelerators provide the luminosity) mass/charge measurement: magnetic field solid angle: need to detect all the outgoing products to completely reconstruct the decays “hermetic” detector (cloud chamber, bubble chamber) track resolution needed both for particle ID and for vertex reconstruction NNPSS 2009 E. Beise, U Maryland 16

CLEO-c: charm quark spectroscopy at Cornell (CESR: e+e- collider) NNPSS 2009 E. Beise, U Maryland 17

the quark model 1950 -1970: explosion of discovery of new “particles”, including antibaryons concepts of isospin, strangeness, baryon number, became useful as organizing/classification scheme ( hypercharge = B+S) charge: Quark hypothesis (Gell-Mann and Zweig, 1964): up, down, and strange Flavor B J I I 3 S charge u 1/3 ½ ½ +1/2 0 2/3 d 1/3 ½ ½ -1/2 0 -1/3 s 1/3 ½ 0 0 -1 -1/3 what are the quark masses? Can we understand them from the spectrum of observed particles? NNPSS 2009 E. Beise, U Maryland 18

hadrons in QCD The strong interaction is defined by the property “color”. This is required to produce bound states with the appropriate symmetry properties (fermion/boson statistics) • The strong interaction is (approximately) flavor independent (same for all quarks, thus, e. g. , same for n and p) • There are 3 types of “color” • The bound states of QCD are only “color neutral”: individual constituents cannot be observed → confinement • The exchange particles (gluons) carry the property of color (and thus can interact with themselves) • The interaction strength decreases with increasing energy → asymptotic freedom NNPSS 2009 E. Beise, U Maryland 19

u and d only: SU(2) flavor symmetry symmetric antisymmetric e. g. , symmetric NNPSS 2009 mixed symmetry: combine with spin part of wave fn to get antisymmetric state: p and n color “neutral”: antisymmetric E. Beise, U Maryland 20

SU(3) and s quarks figure from V. Crede, FSU Mesons: qq Baryons: qqq D-, D 0, D++ p, n S*-, S*0, S*+ S X*- , X*0 W─ NNPSS 2009 S-, S 0 , S+ X- JP=3/2+ (sss) E. Beise, U Maryland , 0 (uds) X 0 JP=1/2+ 21

sss: the WPhys. Rev. Lett. 12, 204 (1964) K+ –e- p e+ e+ K 0 0 X 0 W K– – e- slide from V. Burkert, JLab

masses and magnetic moments The “constituent quark” model can predict these pretty well. p, n 0 S-, S 0 , S+ X- , X 0 (uds) Similar relationships for the JP=3/2+ baryons. These get modified a little by q -q hyperfine structure. Result in “constituent quark” masses: NNPSS 2009 E. Beise, U Maryland 23

heavy quark bound states quark analog of positronium short range nonrelativistic perturbative QCD is not bad e. g. Charmonium: (J/Y) states are very narrow excellent lab to search for exotic and hydbrid bound states (very active: Ba. Bar, Belle, CDF, D 0, …) “Coulombic” NNPSS 2009 confining E. Beise, U Maryland 24

Flux tubes in LQCD Lattice QCD ab initio computation of Baryon masses S. Dürr, et al Science 21 November 2008: 1224 -1227. G. Bali NNPSS 2009 E. Beise, U Maryland 25

Excited baryons simple quark model: harmonic oscillator + some hyperfine splitting… more states predicted than have been found. Are these the correct degrees of freedom? predicted PDG 3 -4 *** PDG 1 -2 *** see X. Ji, U Md Phys 741 lecture notes see also Capstick& Roberts PRD 58 (1998) 074011 NNPSS 2009 E. Beise, U Maryland 26

“Missing” Baryon States Quark models with underlying SU(6)x. O(3) symmetry predict many states, not observed in either hadronic experiments or in meson photo- and electroproduction. Possible solutions: 1. States don’t exist, e. g. di-quark model predicts fewer states, with different underlying symmetry group 2. States exist but have not been found. |q 2 q> Possible reason: they do not couple to N final states… Maybe they decay to other channels: |q 3> K L, K S , p w adapted slide from V. Burkert, JLab

Searches for resonances 2 -body decay: look at the invariant mass distribution. p 1 , m 1 P, M p 2 , m 2 W 2 = M 2 = (p 1 + p 2)2 doesn’t tell you about the quantum #’s Sometimes they overlap 3 -body decay: Dalitz plot p 1 , m 1 P, M p 2 , m 2 p 3 , m 3 beware of artifacts…. . slide from V. Burkert, JLab

Partial Wave Analysis See Dan Carman’s seminar from see last year’s Summer School NNPSS 2009 E. Beise, U Maryland 29

See Dan Carman’s seminar from see last year’s Summer School NNPSS 2009 E. Beise, U Maryland 30

The CLAS Detector at JLab

example of Dalitz Plot: p p. K+KE = 1. 6 -3. 5 Ge. V F(1020) (1520) (1690) slide from V. Burkert, JLab (1820) from the CLAS detector in Hall B at JLab

CLAS Differential & total cross section of γp→K+Λ P 11, P 13, D 13, S 11? Needs polarization observables and measurement in other channels for more definite conclusions. K exchange P 11 P 13 33

Beyond the Quark Model: Hybrids and Exotics slide from R. de. Vita, AAAS meeting, Feb 2008 Quarks combine to “neutralize” color force q q mesons q q q baryons Other quark-gluon configurations can give colorless objects q q q molecule q q tetraquark glueball meson q hybrid meson

pure glue NNPSS 2009 E. Beise, U Maryland from V. Crede, FSU 36

from V. Crede, FSU NNPSS 2009 E. Beise, U Maryland 37

from V. Crede, FSU p+p e+ + e - NNPSS 2009 E. Beise, U Maryland 38

from V. Crede, FSU NNPSS 2009 E. Beise, U Maryland 39

Beyond the Quark Model: Hybrids and Exotics slide from R. de. Vita, AAAS meeting, Feb 2008 Quarks combine to “neutralize” color force q q mesons q q q baryons Other quark-gluon configurations can give colorless objects q q q molecule q q tetraquark glueball meson q hybrid meson

See Dan Carman’s seminar from see last year’s Summer School NNPSS 2009 E. Beise, U Maryland 41

See Dan Carman’s seminar from see last year’s Summer School NNPSS 2009 E. Beise, U Maryland 42

See Dan Carman’s seminar from see last year’s Summer School Exotic Mesons NNPSS 2009 E. Beise, U Maryland 44

The Glue. X Experiment (w/ JLab 12 Ge. V upgrade) Curtis Meyer NNPSS 2006 July 24, 2006 National Nuclear Physics Summer School 45

See Dan Carman’s seminar from see last year’s Summer School NNPSS 2009 E. Beise, U Maryland 46

GSI Helmholtz Center and FAIR PANDA

PANDA Physics Program at the FAIR Facility in Germany Charmonium spectroscopy Exotics: charmed hybrids & heavy glueballs Time-like form factors Medium modifications of charmed mesons Drell-Yan processes Hard exclusive processes CP-violation (D & - sector) Hypernuclei D. Bettoni, GHP 2009 05/01/2009 APS/GHP Meeting, Denver, Colorado

PANDA detector Detector Requirements http: //www. gsi. de/panda NNPSS 2009 E. Beise, U Maryland • (Nearly) 4 solid angle coverage (partial wave analysis) • High-rate capability (2× 107 annihilations/s) • Good PID ( , e, µ, , K, p) • Momentum resolution ( 1 %) • Vertex reconstruction for D, K 0 s, • Efficient trigger • Modular design • Pointlike interaction region • Lepton identification • Excellent calorimetry • Energy resolution • Sensitivity to low-energy photons 50

Summary of this section The quark model laid the groundwork for QCD. The basic spectroscopy of the more easily identifiable bound states of meson and baryon can be characterized by a set of quantum #’s described by the quark model. Searching for new bound states tests the limits, perhaps revealing something deeper about QCD and confinement. Difficult task! Need lots of data taken together with close connection to theory. Opportunities are abundant! NNPSS 2009 E. Beise, U Maryland 51

Hadron Physics Lecture #1: The quark model, QCD, and hadron spectroscopy Lecture #2: Internal structure of hadrons: momentum and spin Lecture #3: Internal structure of hadrons: charge, magnetism, polarizability Lecture #4: Hadrons as laboratories (and other miscellaneous topics) NNPSS 2009 E. Beise, U Maryland 52